Hair tests can detect long-term drug use, but external contamination risks false positives. Advanced analytical equipment now allows precise quantification of drugs in hair at picogram per milligram levels. In a family law case, DMT was found in the hair of a partner of a repetitive DMT smoker at 4 to 13 pg/mg across six 1-cm segments, with concentrations increasing from proximal to distal ends. This pattern and low concentrations indicate environmental contamination rather than ingestion, as older hair had longer contact with the drug. Even after decontamination, environmental drugs can remain bound to hair, enabling documentation of exposure.
A method using liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed to detect psilocin, the active metabolite of psilocybin from magic mushrooms, in human hair. The technique involves incubating 10 mg of hair in acid methanol with a labeled internal standard, followed by chromatographic separation. The method was linear from 1 to 200 pg/mg, with a detection limit of 0.4 pg/mg and good precision. Analysis of hair from a regular magic mushroom user found psilocin levels of 2.5, 4.4, and 5.4 pg/mg in successive 1-cm segments. Cold conditions and protection from light are essential to prevent psilocin degradation during preparation.
Five cases of 3-MeO-PCP use in France in 2018 included two fatalities and three non-fatal cases. The non-fatal cases involved a 36-year-old man with confusion, aggressiveness, logorrhea, and calmness who also tested positive for alcohol, buprenorphine, and tramadol; a man with hyperemesis syndrome; and a methadone user. The fatalities were a 39-year-old woman murdered by ligature strangulation, with 3-MeO-PCP found in femoral blood at 63 ng/mL and urine at 94 ng/mL, and a 41-year-old man found dead at home with femoral blood level 498 ng/mL and urine 16,700 ng/mL. Fatal blood levels in literature range from 50 to 3,200 ng/mL, but clear toxic concentrations are not established due to frequent co-use with other substances.